Answer:
The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north).
Explanation:
The average speed <em>appears to be</em> (distance) / (time) =
(length of the cable) / (time from when a pulse goes in until it comes out the other end) .
That's 1,200,000 meters/ 0.006 second = 2 x 10^8 = <em>2 hundred million m/sec</em>
That figure is about 66.7% of the speed of light in vacuum.
The reason I went through all of this detail was to point out that this is
NOT necessarily the speed of light in this glass, for two reasons.
1). The path of light through an optical fiber is not straight down the middle. In the original fibers of 20 or 30 years ago, the light bounced back and forth off the inside walls of the fiber, and zig-zagged its way along the length. In current modern fibers, it still zig-zags, but it's a more gentle, up-and-down curved path. In either case, the distance covered by the light inside the fiber is more than the straight length of the cable, and the time it takes it to come out the other end is more than its actual speed inside the glass would have meant if it could have traveled straight through the pipe.
2). This problem talks about an optical fiber that's 1,200km long. There is loss in optical fiber, and you're NOT going to get light all the way through a single piece of it that's something like 745 miles long. It takes electronic repeaters, "boosters", and regenerators every few miles to keep it going, and these devices add "latency" or time delay in the process of going through them. That delay in the electronics shows up as apparent delay through the fiber-optic cable, and it makes the speed through the glass appear to be slower than it actually is.
Answer:
a) 
b) 
Explanation:
Given:
- speed of rocket initially,
- top speed of rocket after acceleration,
- time taken to get to the top speed,
- final speed of the rocket,
- time taken to get to the final speed after reaching the top speed,
Now the acceleration:
Now as a fraction of gravity:
Now, the deceleration:
Now as a fraction of gravity:
In a parallel circuit, the total power supply current is the sum of the
currents through all of the individual branches.
The output current (not the voltage) of the power supply is 5 A.
So the individual currents in the circuit branches is 5 A.
The current through the first 2 resistors is (1 + 0.5) = 1.5 A.
So the current through the 3rd resistor is (5 - 1.5) = <u>3.5 A</u>.
Answer:
1000m3
Explanation:
12000=mass*gravity, considerinh gravity 10
12000=mass*10 then mass=1200Kg
With density 1.2Kg/m3
1.2Kg ... 1m3
1200Kg ... 1000m3
End
